Telephone apparatus.



. G. H. VIGGARS & E. H. STOLZ.

TELEPHONE APPARATUS.

APPLICATION IILBD un. 1a, 1903.

91 1,531 Patented Feb. 2, 1909.

UNITED STATES PATENT OFFICE.

c anges 15;. vrce aas AND. ERNEST a. srroriz, or CHICAGO, ILLINOIS; sun VIGGARS ssxcuoa 'ro s n) sToLz,

'IQELEBHONE APPA ATUS,

Specification of Letters Patent.

Patented Feb. 2, 1909.

Application filed January 13, 1908. Serial No. 410,604.

To all whom it may concern:

Be it known that we, CHARLES H. VIG- cans and ERNEST SToLz,'said Vrooaas being a subject of the King of Great Britain and said SroLz a citizen of the United States of America, and both being residents of Chicago, county of Cook, State of Illinois, have invented certain new and useful Improvements in Telephone Apparatus, of which the following is a specification.

The main ob'ects of this invention are to rovide a simple, inexpensive and improved .orm of telephone apparatus particular];

adapted for use in assisting the deaf to hear; to provide a construction for apparatus of this character which will permit of attaching the transmitter directto the battery i icaseswhere it. is desire to support the transmitter from the battery whilejheid in a pocket of 'thefwearer, which will also permit a connection to be inserted between the transmitter and battery so that the transmitter may be attached to the clothing of the wearer at some distance from the battery, and also to thus enable the user to use a larger battery than could be carried in'the same pocket with the transmitter; to provide an improved construction forthe concentrator which directs the sound vibrations toward the transmitter diaphragm, whereby the concentrator may be rea ily removed or attached to the casln and to provide an improved form of ei earede with an improved arrangement of ranules capable of causing intensified repro notion of comparatively faint sounds originating at a considerable distance from the transmitter. These objects are accomplished by the device shown in the accompanying drawings, in which Figure 1 is an elevation illustrating the general arrangement of the apparatus. Fig. 2 is an elevatlon of the transmitter and battery, showing their terminals directly connected together. Fig. 3 is a.rear elevation of the transmitter, with the back of the casing partly broken away to disclose the arrangement of the parts within. Fig. 4 is a transverse section of the transmitter on the line A-A of Fig. 3. Fig. 5 is a front elevation of the inner electrode, showing the arrange ment of the granule retaining pockets.

In the form shown in the drawing, the apparatus comprises a batte 1, a transmitter 2, and a receiver 3. T e receiver is connected with the transmitter in the usual manner by means of a flexible conductor 4. the transmitter and battery are also connected by a flexible conductor cord 5 which is detachably connected at. one end to the binding posts 6 and 7 of the transmitter, and its other end is provided with socket members 8 adapted to be clamped to the terminal studs 9 of the battery. The studs 9 are. spaced the same distance apartas the binding posts 6 and 7 and are so disposed as to be capable of being directly connected to gether, as in Fig. 2, when the cord 5 is removed. It is preferred to make the studs 9. of diiiercnt diameters, as illustrated, and to sake the sockets in the binding posts 6 and 7 corresponding in size to their respective studs so as to prevent the possibility of improplerly connecting the parts together.

T e. transmitter comprises. a casing formed of a front part 10 and a back part 11 secured together. The middle of the front face of the part 10 is slightly concave and has a perlorated area to admit sound waves to the interior of the casing. Sound waves are directed toward this area by a sound concentrator or megaphone 13 which is formed of resilient material and provided with a pair of prongs 14 adapted to be sprung into two of the apertures of said perforated area for retaining the concentrator in position. Each of the. apertures 12 in said perforated area is conical'in form and tl-a'es outward like a megaphone. i i

A iaphraginl, usually of carbon, so that it will serve as one of the electrodes of the transmitter circuit, is seated on an annular shoulder 16 within the casing and is secured in position by means of a ring 17, being held between gaskets. The gasket 18 is of metal and serves as a contact connecting the diaphragm with the circuit through the wire 23, Fig. -l. The casing and ring 17 are prcferably formed of insulating material such as hard rubber, the ring being held in position through threaded engagement with the front partlO of the casing. The inner electrode 19 consists of a block of carbon mounted with it's fiat front face near and paralle with the diaphragm 15. The electrode 19 is preferabl mounted upon a bar 20, which is rigidly astened diametrically across the ring 17 and which has one end extended outward of the casing, carrying thereon the terminal binding post 6.

The electrode 19 has a plurality of cylindrical granule-retaining sockets 21, each inclined inwardly and upwardl 'from the front face of the electrode. ithin these sockets are seated the granules by means of which the resistance of the electric circuit is varied so as to produce the desired reproduction of sound at the receiver. In this apparatus the granules are preferably true spherical pellets of carbon, and all those in the same socket are of uniform diameter. The sockets are of a diameter loosely fitting the granules, so that each socketwill contain a single row of granules resting one upon the other, the lowest granule being sup ported at the mouth of the socket through its contact with the diaphragm 15. The uppermost pellet is in each case of lead or some other conducting; material heavier than carbon, so as to increase the inertia of the row of pellets and thereby increase the range of variation in pressure between adjacent pellets duringthe vibratirof the diaphragm. The space between rue electrodes is, of course, less than the diameter of the granules.

The binding post 7 is carried by a bar 22 which is fastened to the ring 17, and the conductors 23 and 24 of the cord 4 are respectively connected with the diaphra lnelectrode and the bar 22, as 'will be un erstood from Fig. 3.

The casing is provided with a suspending eye 25 which is adapted to be hung from a suitable fastener, such as, for instance, that shown in Fig. 4, which is in the form of a safety pin 26 arranged for attachment to the wear ers clothing.

The operation of the device shown is as follnws:'lhe transmitter and battery are capable of either direct connection, as in Fi i 2, or indirect connectlon through a flexible conductor, as in Fig. 1, to suit the circumstances under which the apparatus is to be used. In cases where the transmitter may be carried in the same pocket in which the battery is'carried, the two may be directly connected; while in cases Where it is referred to place the transmitter where it is more exposed to the sound waves, it may be attached to some convenient part of the users clothing and connected to the battery in his pocket by means of the flexible conductor 5.

The sockets 21 are not completely filled with granules, so that when the diaphragm vibrates, the granules will roll along their sockets in contact with the walls thereof and with each other. The movements of the diaphragm and its effect on the granules causes changes in the resistance of the electric circuit; which in turn operates the receiver in the well known manner.

What we claim as our invention and desire to secure by Letters Patent is:

In a device of the class described, the combination of a pair of electrodes, one of said electrodes being formed of carbon and having in its front face a plurality of cylindrical sockets inclined upward] from the other electrode and extending oni y part Way through said first electrode, a single row of "ranules in each of said sockets, each of such 'iameterthat it will loosely fit within its socket, and. an electric circuit including said granules and adapted to have its resistance varied through the relative movement of said electrodes toward and away from each other.

Signed at Chicago this 8th day of January, 1908.

CHARLES H. VIGGARS. ERNEST H. STOLZ.

\Vitnesses E. A. RUMMLER, MARY M. DILLMAN. 

